https://thinkhard.si/blog/ Notes on writing, testing and paying for prompts at work. en-us https://thinkhard.si/blog/ai-dcf-valuation/https://thinkhard.si/blog/ai-dcf-valuation/Wed, 21 Oct 2026 09:00:00 GMTA language model reads filings and argues with your story well, and it should never compute a discount factor or supply a share count. https://thinkhard.si/blog/ai-writes-like-a-brochure/https://thinkhard.si/blog/ai-writes-like-a-brochure/Wed, 21 Oct 2026 09:00:00 GMTBrochure prose fills the space where facts should be, so take the style words out of your prompt and put the facts, the reader and a length in. https://thinkhard.si/blog/system-prompt-contract/https://thinkhard.si/blog/system-prompt-contract/Tue, 20 Oct 2026 09:00:00 GMTScope, sources of truth, promises the bot may not make, refusals, escalation and injection defenses, written as clauses you can test. https://thinkhard.si/blog/support-chatbot-cost/https://thinkhard.si/blog/support-chatbot-cost/Fri, 16 Oct 2026 09:00:00 GMTTurn-by-turn arithmetic on six models shows why conversation history drives the bill, what caching and batch save, and why cost per resolved conversation is the number to watch. https://thinkhard.si/blog/cheapest-model-that-passes/https://thinkhard.si/blog/cheapest-model-that-passes/Wed, 14 Oct 2026 09:00:00 GMTSet the bar first, test across price tiers and count what failures cost, because at list prices the same job can cost 100 times more on a top model. https://thinkhard.si/blog/prompts-are-sops/https://thinkhard.si/blog/prompts-are-sops/Mon, 12 Oct 2026 09:00:00 GMTThe prompts that answer customers and route tickets are company procedures, so give each one an owner, a version, a test suite and a review date. https://thinkhard.si/blog/why-ai-answers-change/https://thinkhard.si/blog/why-ai-answers-change/Fri, 09 Oct 2026 09:00:00 GMTTemperature zero will not make answers repeatable, so decide where variation is a bug and test across many inputs and repeated runs. https://thinkhard.si/blog/make-it-better/https://thinkhard.si/blog/make-it-better/Wed, 07 Oct 2026 09:00:00 GMTVague prompts cost hours of rework and confused readers, and a short brief that says what is wrong and what good looks like fixes both. https://thinkhard.si/blog/ai-tool-or-better-prompt/https://thinkhard.si/blog/ai-tool-or-better-prompt/Mon, 05 Oct 2026 09:00:00 GMTMany AI tools are a hidden prompt and a text box, so here is how to tell when a good prompt is enough and when a product earns its price.